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A method of surfactant-mediated photovoltaic transportation is proposed in this paper, the surfactant (span 80) layers self-assembled at the water-oil and oil-LN interfaces are employed to isolate photovoltaic charges in this method. The reduced electrostatic attenuation, remarkable hydrophobicity, and strong electrical breakdown suppression of the surfactant layers enable the stable and swift transportation of fL-scale aqueous microdroplets using μW-level laser in an oil medium. Three kinds of microdroplet responses to the laser illumination (unresponsive, repulsive and attractive cases) was found. With the increase of surfactant concentration, the driving mechanism can transit from the coulomb repulsion to the dielectrophoretic attraction that facilitates the photovoltaic transportation. Besides, the minimal laser power required for the attractive response was found correlated with the NaCl concentration inside the microdroplet. [ABSTRACT FROM AUTHOR]

The extensive generation of coal dust during underground mining operations has resulted in adverse working conditions, significantly elevating the occurrence of safety accidents, and posing health risks to coal miners. This paper explores the synergistic enhancement and wetting behavior of a selected composite surfactant solution when combined with four distinct types and concentrations of inorganic salt solutions. Various experimental methods were employed to investigate the interactions and wetting characteristics. The findings demonstrate that a composite solution consisting of 0. 9 mol/L NQ2SO4 with a combination of SDBS and Triton X 100 at a ratio of 4 : 1 exhibits the most favorable synergistic effect. Furthermore, a quantitative evaluation of the wetting performance parameters of the coal was based on the results obtained. It was observed that the spreading coefficient correlates positively with Na2SO4 concentration, while both adhesion work and surface free energy show a negative correlation with Na2 SO4 concentration, which suggests that the introduction of inorganic salt anions restores the absorbability of kaolinite, increasing the number of hydrophilic sites on the coal surface and enhancing the adsorption density of anion nonionic composite surfactants. Consequently, the wetting performance of the solution is significantly improved. [ABSTRACT FROM AUTHOR]

Based on the advantages of high storage capacity, simple preparation conditions and stable storage,hydrate technology is widely used in many fields, such as storage and transportation of natural gas, gas separation, cold storage, etc. However, the low formation rate of pure hydrate and low gas storage density are the main reasons that hinder the industrial application of hydrate technology, research has shown that adding surfactants to the system can effectively alleviate and ameliorate this problem. This paper reviews the research development of ionic surfactants at home and abroad, analyzes their effects on the phase equilibrium conditions, formation rate and gas storage density of hydrate formation, the acceleration mechanism of various surfactants on hydrate synthesis are described in detail, which provides theoretical reference for further research of hydrate theory and technology and industrial development. [ABSTRACT FROM AUTHOR]

In this paper, reactive carbamate surfactants (RCS-10) have been synthesized using stearyl alcohol polyoxyethylene ether (AEO) and 2-isocyanatoethyl methacrylate (IEM), and characterized using Fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance (¹H-NMR). And the critical micelle concentration (CMC) of RCS-10 was 5. 19 X10-4 mol/L, which was measured by surface tension method at room temperature. Additionally a novel hydrophobically associative polymer has been synthesized by copolymerizing RCS-10 with acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, and acrylic acid, and the rheological properties of its aqueous solution have been analyzed. The results showed that the modified and unmodified polyacrylamide solutions exhibit viscosity retentions of 97.73% and 87.07%, respectively, at 120 °C under a shear rate of 170 s-1. Thus, RCS-10 polymerization improves the heat and shear resistance and the storage and loss moduli of the polyacrylamide, indicating a structural-stability enhancement on polymerization. Therefore, RHPAM exhibits high potential to improve the heat and shear resistance of fracturing fluids and enhance oil recovery. [ABSTRACT FROM AUTHOR]

In this paper, single factor and orthogonal experiments were used to explore the influence of abrasive grain types, polishing slurry pH value, surfactant type, and abrasive grain size on the removal rate of C-plane sapphire chemical mechanical polishing materials. The test results show that: a higher material removal rate and a better surface morphology can obtained when using silica as abrasive particles; the material removal rate shows a trend of first increasing and then decreasing with the increase of the pH value of the polishing slurry, and the pH value of the 9 attachment can get a better removal rate; the material removal rate also increases with the increase of abrasive particle size; using triethanolamine (TEA) and cetyltrimethylammonium bromide (CTAB) as surfactants can get a higher material removal rate; the primary and secondary order of each test factor on the removal rate of sapphire wafer material is abrasive particle size, surfactant, polishing slurry pH value; when the abrasive particle size is 50 nm, the surfactant is CTAB, and the polishing slurry pH value is 9 can get higher material removal rate and better surface quality. [ABSTRACT FROM AUTHOR]

In this paper, the preparation methods and characteristics of nickelbased nanocomposite coatings were reviewed. Process conditions affected the composite amount and distribution of nano particles in the coating. The effects of surfactant, pH value, current density and bath temperature on nickel-based nanocomposite coatings were analyzed. Then the applications of nickel-based nanocomposite coatings in several main fields were introduced. Finally, through the study of the present research about nickel-based nanocomposite coatings, the research emphases and development direction in the future were prospected. [ABSTRACT FROM AUTHOR]

Tn this paper, the effect of surfactant on the settling stability of magnetorheological fluid was mainly studied. The differences in the properties of magneto-rheological fluid samples with different kinds and mass fraction of surfactants were analyzed through experiments to explore the influence of surfactant HLB value on the anti-settling stability of magneto-rheological fluid. Tt was found that the settling stability of magneto-rheological fluid was improved with the decrease of HLB value. Tn addition, the concept of contact angle was also introduced to analyze the influence of measuring dispersed particles on wettability of base liquid in the preparation process of magnetorheological fluid, and to explore a new evaluation method based on magnetorheological fluid 's anti-settling stability. [ABSTRACT FROM AUTHOR]

The concept of volume fracturing has brought about a technological revolution in the exploration and development of unconventional oil and gas resources. The theory of micro-fracture imbibition and displacement has changed the traditional understanding of the fracturing fluid industry. In this paper, the Gemini surfactant was synthesized by the molecular design, and the acetylenic alcohol nanosilica oil release agent was optimized and matched, then the oil displacement surfactant fracturing fluid was developed. Compared with the conventional guanidine gum fracturing fluid system, the system has better dispersion and wettability change performance, with an osmotic efficiency of 38% and an oil displacement efficiency of more than 20%. The on-site test shows that the oil speed is fast, the output at the initial stage of production is high, the water content is low, and the effect of increasing production is obvious. [ABSTRACT FROM AUTHOR]

In this paper, hexadecylethylenediaminetriacetic acid (HKD3A) was used as the surfactant to prepare gold nanometer flowers for the first time. The appearance of gold nanometer flowers could he effected by the concentration of HED3A, ascorbic acid(AA) and chloroauric acid(HAuCl4)and the reaction temperature. The results showed that under the same conditions, when the concentration of HED3A increased from 0. 1 mmol/L to 50 mmol/L, the gold nanoparticles changed from flower to sphere; When the concentration of ascorbic acid increased from 0. 06 mol/L to 0.2 mol/L, the gold nanoflowers from density to loose; when the concentration of HAuC14 increased from 0.5 mg/ml to 3 mg/ml, the gold nanoparticles changed from spherical to flower; when the temperature increased from 20 °C to 80 °C, the gold nanoparticles changed from flower to sphere. The morphology of gold nanoparticles remained unchanged after 12 months. The surface enhanced Raman spectrum (SERS) of Rhodamine 6G(R6G)was detected to 10 nmol/L and the gold nanometer flowers were proved non-toxic. The above results show that the surfactant can effectively control the morphology of gold nanoflowers, and the obtained gold nanoflowTers may be a potential Raman enhanced substrate and biomedical materials. [ABSTRACT FROM AUTHOR]

Surfactant flooding is one of the most important techniques for improving recovery of low permeability reservoirs. The performance of the surfactant in reducing oil and water interfacial tension was emphasized in the past, but the emulsifying properties of the surfactant were not paid enough attention. For the study of emulsion performance influence on improving recovery of low permeability reservoirs in this paper, two kinds of surfactants with the same ultra-low interfacial tension and different emulsification ability are selected in combination with the conditions of Changqing oilfield low permeability reservoir, and the experiment of flooding oil displacement is carried out by using homogeneous and non-homogeneous cores. Experimental results show that, with ultra-low interfacial tension and strong emulsifying ability, BA can reduce the seepage resistance in the core entry section and realize the effect of emulsification sealing in the center of the core, the residual resistance coefficient of central core is 2.08. The surfactant TS with ultra-low emulsification ability of interfacial tension can not establish flow resistance, which can only play the role of reducing pressure. In the experiment of the non-homogeneous core, 0.6 PV BA active agent segment, established the displacement pressure, expanded the conformance coefficient, and the recovery rate increased by 11.46%. The recovery rate of the active agent TS was 5.88%. [ABSTRACT FROM AUTHOR]

Taking the tight sandstone reservoir of the upper Triassic, Xu Jiahe group in the Sichuan central region as an example, combing with the reservoir numerical simulation, then analyzing the qualitative and quantitative influences of injection rate, injection concentration of surfactant, injection PV number on the recovery efficiency of tight sandstone reservoir, this paper focuses on the problem of the tight oil reservoir’s low recovery, and also forecasts the effect of the different surfactant flooding scheme, then presents the best plan in this reservoir condition, and acquires the main control factors of the surfactant flooding. [ABSTRACT FROM AUTHOR]

Bubble-mineral particles attachment and mineralization process are critical to flotation technology which can realize the effective separation of coal and gangue. It is indispensable for understanding the mechanism of mineralization process in flotation to investigate the interaction between low rank coal particles and reactive oily bubbles by electrochemistry studies and induction time measurements. In this paper, the influence of pH of solution and surfactants on the interaction between low rank coal particles and reactive oily bubbles which can be estimated by the DLVO theory was investigated. And the attachment efficiency was evaluated by the induction time measurements. The results showed that the isoelectric point (IEP) of coal particles and diesel oily bubbles was observed over the range of pH 2-3 and pH 3-5, respectively. No interaction energy barrier between coal particles and diesel oily bubbles was observed in the tested solution of pH 3, while the interaction energy barrier appeared and gradually increased with the increase of pH value when it exceeded 3. It indicated that the interaction energy barrier and induction time between coal particles and diesel oily bubbles modified by surfactants 2-ethylhexanol and didodecyldimethylammonium bromide were lower than diesel oily bubbles, with the maximum decrease of 74.35% and 86.45% respectively. [ABSTRACT FROM AUTHOR]